In recent years, with the rapid development of urban rail transit, energy saving in urban rail transit systems has attracted attention. The energy consumption of a rail transit system includes power used in dynamic electricity controlling and lighting and power used in train traction. Power used in train traction is reduced mainly by two methods: one is a single-train energy-saving operation method in which a single train is taken as the object to be controlled, so as to optimize the strategy for driving the train between stations; the other is a train group optimization control method in which maximizing utilization of regenerative energy is taken as the optimization objective.
Regenerative energy comes from regenerative braking. Regenerative braking is a technique of converting the kinetic energy of a vehicle into electric energy. The converted electric energy may be fully used by reasonably arranging the sequence of train traction/braking in a train group. In urban rail transit, it is easy for up trains and down trains near the same station to form a scene on which one train is braking while the other is in a traction state. The two trains forms a matched pair of trains, and regenerative energy may be fully used by adjusting the running strategy of the matched pair of trains.
The optimization of train control often focuses on optimizing the running profile of a single train or a train group, and people fail to provide a train control method for maximizing utilization of regenerative energy by optimizing the running profiles for the matched pair of trains at the same station.